1. Field of the Invention
The invention relates to a dosing device for gas chromatography with a dosing plunger which can be moved axially between a sampling position in the sample stream and a delivery position in a sample evaporation chamber connected to the separation column, and which is provided with a dosing volume measuring means in the form of a recess in the shank of the plunger.
2. The Prior Art
Devices are known for preparing liquid samples for gas chromatography analysis in which it is desired to evaporate the liquid sample in an electrically heated evaporation chamber as quickly and completely as possible so that the gas can be fed to the separation column without delay to obtain better separation results.
Difficulties arise, however, if sample liquids with a high boiling point are to be evaporated; the high temperatures required for this purpose can be obtained in the externally heated evaporation chamber only with difficulty at the rate of temperature rise necessary for the sudden evaporation. The maximum evaporation temperature is also limited by the critical heat-carrying capacity of the materials of the device, particularly of the seals in the plunger feedthroughs.